Include the PPC jit in the project.

So it's easier to find when refactoring.
Prevent a crash in debugger without jit.
Fix InvalidateICache() breaking binary searching.
Just invalidate blocks on ClearCacheAt().

This makes it safe to call from a jitted syscall, etc.
Invalidate stubs/var imports when writing them.
Keep unknown syscall reporting the same.

Oops.
Cleanup comment (broke savestates anyway.)
Merge pull request #3544 from unknownbrackets/module-imports

Invalidate icache on stub/var import update